Serge Bakchine

Social cognition impairments in relapsing-remitting multiple sclerosis.

Theory of Mind (ToM) is the ability to attribute independent mental states to self and others to explain and predict behavior. Impairment of ToM is well established in developmental pathologies. In neurological populations, investigation of ToM is still rare but data suggest that ToM impairment could contribute to behavioral and social disturbances. In addition to neurological signs, multiple sclerosis (MS) presents with disorders of cognition and behavior directly related to brain damage. The aim of this study was to assess ToM abilities and recognition of facial emotional expression in adults with MS. We compared 64 patients with relapsing MS and 30 matched healthy controls on three levels of ToM tasks, a facial emotion recognition task, and a neuropsychological assessment. MS patients performed significantly worse than controls in emotion recognition and all ToM tasks (p < .02). These deficits were not correlated with demographic variables or neuropsychological test performance. These findings underscore the importance of assessing ToM and facial recognition in MS, as dysfunction in these areas may impact upon social interaction and, thus, impair quality of life for both patients with MS and their families.

Apathy and Depression in Mild Alzheimer's Disease: A Cross-Sectional Study Using Diagnostic Criteria

Apathy and depression are the most frequent neuropsychiatric symptoms in Alzheimers disease (AD). In a cross-sectional observational study of 734 subjects with probable mild AD, we evaluated the prevalence of apathy and depression. After the use of specific diagnostic criteria, we tested the interaction between the two syndromes and their relation with specific comorbidities, and different functional outcomes. Depression was diagnosed using the diagnostic criteria for depression in AD, and apathy with the diagnostic criteria for apathy in neuropsychiatric disorders. According to the specific diagnostic criteria, depression had a 47.9% prevalence, while apathy prevalence was 41.6%. Apathy and depression were associated in 32.4% of patients (n = 225). 9.4% (n = 65) had only apathy, 15.4% (n = 107) had only depression, and 42.9% had no apathy and no depression (n = 298). The three most frequent depressive symptoms were fatigue or loss of energy (59.4%), decreased positive affect or pleasure in response to social contacts and activities (46.2%), and psychomotor agitation or retardation (36.9%). Concerning apathy, loss of goal-directed cognition was the most frequently altered (63.6%), followed by loss of goal-directed action (60.6%) and loss of goal-directed emotion (43.8%). Patients with both apathy and depression more frequently required a resource allowance for dependency. Neurological comorbidities were more frequent in the apathy and depression and depression alone groups (p < 0.001). Apathy and depression overlap considerably, and this might be explained by the presence of some non-specific symptoms in both diagnostic criteria. The need for social support is higher when a patient fulfills the two diagnostic criteria.

Dissociation of emotional processes in response to visual and olfactory stimuli following frontotemporal damage.

Contemporary neuropsychological studies have stressed the widely distributed and multicomponential nature of human affective processes. Here, we examined facial electromyographic (EMG) (zygomaticus and corrugator muscle activity), autonomic (skin conductance and heart rate) and subjective measures of affective valence and arousal in patient TG, a 30 year-old man with left anterior mediotemporal and left orbitofrontal lesions resulting from a traumatic brain injury. Both TG and a normal control group were exposed to hedonically valenced visual and olfactory stimuli. In contrast with control subjects, facial EMG and electrodermal activity in TG did not differentiate among pleasant, unpleasant and neutral pictures. In addition, the controls reacted spontaneously with larger corrugator EMG activity and higher skin conductance to unpleasant odors. By contrast, the subjective feeling states (pleasure and arousal ratings) remained preserved in TG. The covariation between facial and self-report measures of negative valence was also a function of the nature of the olfactory task in the patient only. Taken together, the data suggest a functional dissociation between brain substrates supporting generation of emotion and those supporting representation of emotion. We thank TG and the subjects of the control group for their participation in this research.

Juvenile Frontotemporal Dementia with Parkinsonism Associated with Tau Mutation G389R

Frontotemporal lobe degeneration includes a large spectrum of neurodegenerative disorders. Patients with frontotemporal dementia with parkinsonism linked to chromosome 17 exhibit heterogeneity in both clinical and neuropathological features. Here, we report the case of a young patient with a G389R mutation. This teenager girl was 17 years old when she progressively developed severe behavioral disturbances. First, she was considered to be suffering from atypical depression. After 2 years, she was referred to the department of neurology. By this time, the patient exhibited typical frontotemporal dementia with mild extrapyramidal disorders. The main behavioral features included apathy and reduced speech output. MRI and SPECT showed a frontotemporal atrophy and hypofixation, respectively. She died 7 years after onset. Three relatives on her father side had also died after early onset dementia. Genetic testing revealed a heterozygous guanine to cytosine mutation at the first base of codon 389 (Exon 13) of MAPT, the tau gene, resulting in a glycine to arginine substitution, in the patient and her non-affected father. Postmortem neuropathological and biochemical data indicate a Pick-like tau pathology but with phosphoserine 262-positive immunoreactivity. This case is remarkable because of the extremely early onset of the disease.

Endostatin Level in Cerebrospinal Fluid of Patients with Alzheimer's Disease

The aim of this study was to measure the level of endostatin, a fragment of collagen XVIII that accumulates in the brain of patients with Alzheimers disease (AD), in the cerebrospinal fluids (CSF) of patients with neurodegenerative diseases. The concentrations of total protein, endostatin, amyloid-β1-42 peptide, tau, and hyperphosphorylated tau proteins were measured by enzyme-linked immunosorbent assay in CSF of patients with AD (n = 57), behavioral frontotemporal dementia (bvFTD, n = 22), non AD and non FTD dementia (nAD/nFTD, n = 84), and 45 subjects without neurodegenerative diseases. The statistical significance of the results was assessed by Mann-Whitney and Kruskal and Wallis tests, and by ROC analysis. The concentration of endostatin in CSF was higher than the levels of the three markers of AD both in control subjects and in patients with neurodegenerative diseases. The endostatin/amyloid-β1-42 ratio was significantly increased in patients with AD (257%, p < 0.0001) and nAD/nFTD (140%, p < 0.0001) compared to controls. The endostatin/tau protein ratio was significantly decreased in patients with AD (-49%, p < 0.0001) but was increased in bvFTD patients (89%, p < 0.0001) compared to controls. In the same way, the endostatin/hyperphosphorylated tau protein ratio was decreased in patients with AD (-21%, p = 0.0002) but increased in patients with bvFTD (81%, p = 0.0026), compared to controls. The measurement of endostatin in CSF and the calculation of its ratio relative to well-established AD markers improve the diagnosis of bvFTD patients and the discrimination of patients with AD from those with bvFTD and nAD/nFTD.

Social Cognition Abilities in Patients With Different Multiple Sclerosis Subtypes

OBJECTIVESnMultiple sclerosis (MS) can be associated with impaired social cognition. However, social cognition skills have never been explored in the different subtypes of MS. The first aim of this study was to examine whether MS subtypes differ on the course of social cognition. The second aim was to explore the relationship between social cognition performances and executive abilities and mood variables.nnnMETHODSnSixty-two patients with MS and 33 healthy matched controls performed experimental tasks assessing facial emotion recognition, theory of mind (ToM), and cognitive functioning, in particular executive functions.nnnRESULTSnPatients differed from controls on both measures of social cognition. On the ToM measures, patients with progressive MS scored significantly lower than healthy participants. Patients with primary progressive MS performed worse than both healthy participants and patients with relapsing-remitting MS on the recognition of fearful facial expressions, while patients with secondary progressive MS performed worse on the recognition of facial expressions of sadness. Patients social cognition difficulties were correlated with processing speed, working memory, and verbal fluency.nnnCONCLUSIONSnThese preliminary results suggested that there may be qualitative differences in social cognition difficulties among the phenotypes. Furthermore, these impairments were related to executive functions, but unrelated to patients disability or level of depression. These data highlight the need for research to determine the real impact of these deficits on interpersonal relationships among patients and to confirm these disorders in a larger population with progressive forms of MS. (JINS, 2017, 23, 653-664).

When synesthesia and savant abilities are mistaken for hallucinations and delusions: contribution of a cognitive approach for their differential diagnosis

Abstract Objective: Schizophrenia is characterized by hallucinations, delusions, disorganized speech and behavior, and other symptoms that cause social or occupational dysfunction. However, some of these symptoms, such as hallucinations and delusions, can be indicative of other phenomena such as synesthesia and savant abilities. The aim of this paper is to highlight how neurological and psychiatric conditions can be confused and how formal neuropsychological evaluations can be necessary to distinguish them. Method: We report the case of a young woman, VA, who perceived sounds as colors and claimed to have elaborated complex astrophysical reasoning, despite having experienced difficulties at school, especially in mathematics. VA also had difficulties to orient herself, to develop social relationships, and often became confused by daily life situations. These elements were considered as symptoms of schizophrenia. Results: Evaluations revealed that VA exhibited savant abilities in astrophysics and colored-hearing synesthesia. We also found evidence of higher-than-average cognitive functioning. Conclusions: In complex cases, neuropsychological and formal evaluations are necessary to establish a differential diagnosis. Moreover, the case highlights the link between synesthesia and savant abilities.